I am looking at purchasing a house and it has a sun room that I would like to turn into a functional living area. I was wondering about the process and cost to raise the floor to use it. any help and ideas would be greatly appreciated.

Welcome to the site. As this was a garage before it was a room there are some thing you want to think about before you raise the floor.
There is a good chance there is void in the foundation where the big door was and then water can get under the deck and likely the driveway is still there you could have a flood on top of this deck.
Did you want to level the floor or raise it to match the house floor and how high is that?